Automotive and GM Financial Debt Automotive and GM Financial Debt (Details) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Automotive [Member]
Debt Instrument [Line Items]
Carrying Amount	$ 10,752,000,000	$ 8,765,000,000
Fair Value	11,612,000,000	9,088,000,000
Available under credit facility agreements	$ 14,035,000,000	$ 12,168,000,000
Weighted Average Interest Rate on Outstanding Short-term Debt	10.50%	9.60%
Weighted Average Interest Rate on Outstanding Long-term Debt	5.20%	4.70%
Net Discount and Debt Issuance Costs	$ 499,000,000	$ 549,000,000
Automotive [Member] \| Secured Debt [Member]
Debt Instrument [Line Items]
Carrying Amount	136,000,000	220,000,000
Automotive [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Carrying Amount	9,795,000,000	7,619,000,000
Automotive [Member] \| Level 1 [Member]
Debt Instrument [Line Items]
Fair Value	9,515,000,000	6,972,000,000
Automotive [Member] \| Level 2 [Member]
Debt Instrument [Line Items]
Fair Value	2,097,000,000	2,116,000,000
GM Financial [Member]
Debt Instrument [Line Items]
Carrying Amount	73,876,000,000	54,346,000,000
Fair Value	74,577,000,000	54,397,000,000
GM Financial [Member] \| Secured Debt [Member]
Debt Instrument [Line Items]
Carrying Amount	39,270,000,000	30,689,000,000
Fair Value	39,357,000,000	30,671,000,000
GM Financial [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Carrying Amount	34,606,000,000	23,657,000,000
Fair Value	35,220,000,000	23,726,000,000
GM Financial [Member] \| Level 2 [Member]
Debt Instrument [Line Items]
Fair Value	69,990,000,000	48,716,000,000
GM Financial [Member] \| Level 3 [Member]
Debt Instrument [Line Items]
Fair Value	4,587,000,000	5,681,000,000
Capital Lease Obligations [Member] \| Automotive [Member]
Debt Instrument [Line Items]
Carrying Amount	821,000,000	$ 926,000,000
Capital Lease Obligations [Member] \| GM Financial [Member]
Debt Instrument [Line Items]
Carrying Amount	$ 0
Minimum [Member] \| Automotive [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	0.00%	0.00%
Maximum [Member] \| Automotive [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	18.00%	18.00%

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of unamortized debt discount (premium) and debt issuance costs.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Weighted average interest rate of long-term debt outstanding.

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